Fluid flow control with transformation media.

We introduce a new concept for the manipulation of fluid flow around three-dimensional bodies. Inspired by transformation optics, the concept is based on a mathematical idea of coordinate transformations and physically implemented with anisotropic porous media permeable to the flow of fluids. In two situations-for an impermeable object placed either in a free-flowing fluid or in a fluid-filled porous medium-we show that the object can be coated with an inhomogeneous, anisotropic permeable medium, such as to preserve the flow that would have existed in the absence of the object. The proposed fluid flow cloak eliminates downstream wake and compensates viscous drag, hinting at the possibility of novel propulsion techniques.

Observations of spatial flow patterns at the coral colony scale on a shallow reef flat

Although small-scale spatial flow variability can affect both larger-scale circulation patterns and biological processes on coral reefs, there are few direct measurements of spatial flow patterns across horizontal scales <100 m. Here flow patterns on a shallow reef flat were measured at scales from a single colony to several adjacent colonies using an array of acoustic Doppler velocimeters on a diver-operated traverse. We observed recirculation zones immediately behind colonies, reduced currents and elevated dissipation rates in turbulent wakes up to 2 colony diameters downstream and enhanced Reynolds stresses in shear layers around wake peripheries. Flow acceleration zones were observed above and between colonies. Coherent flow structures varied with incident flow speeds; recirculation zones were stronger and wakes were more turbulent in faster flows. Low-frequency (<0.03 Hz) flow variations, for which water excursions were large compared with the colony diameters (Keulegan-Carpenter number, KC >1), had similarspatial patterns to wakes, while higher-frequency variations (0.05-0.1 Hz, KC<1) had no observable spatial structure. On the reef flat, both drag and inertial forces exerted by coral colonies could have significant effects on flow, but within different frequency ranges; drag dominates for low-frequency flow variations and inertial forces dominate for higher frequency variations, including the wave band. Our scaling analyses suggest that spatial flow patterns at colony and patch scales could have important implications or both physical and biological processes at larger reef scales through their effects on forces exerted on the flow, turbulent mixing, and dispersion. © 2013. American Geophysical Union. All Rights Reserved.

Transcultural satire in German fiction of Turkish migration: Self-deprecation, ethnic impersonation, intertexuality

My dissertation presents a study of satire in contemporary German Fiction of Turkish migration. Engaging with a body of works hitherto neglected in scholarship, I examine how satirical texts, films, and plays intervene critically in discourses on post-unification German national identity. Drawing on the seminal work of scholars such as Leslie Adelson, Tom Cheesman, B. Venkat Mani, Petra Fachinger, and Deniz Göktürk, my dissertation expands the scholarship of Turkish German Studies by linking a discussion of satire as a critical rhetoric to the question of how we talk about what it means to be German.

Chapter one offers a novel framework of the satirical vis-à-vis standard conceptions of satire and deconstructionist theories of reading. I understand satire as a form of rhetoric that creates moments of ambiguity by bringing together intersectional categories like gender, ethnicity, race, religion, in order to challenge the audience’s practices of interpreting cultural otherness. Chapter two examines the use of ethnic self-deprecation as one such strategy in Osman Engin’s short stories and his first novel, Kanaken-Ghandi through the lens of Bakhtinian polyphony and Judith Butler’s work on hate speech. Engin, I argue, employs ethnic selfdeprecation as a narrative strategy to straddle the line between deconstructing and re-affirming cultural stereotypes. Investigating the role of ethnic impersonation in Hussi Kutlucan’s film Ich Chef, Du Turnshuh, the third chapter turns to the question of ethnicity as a visual signifier for the negotiation of cultural inclusion and exclusion in post-1990 film. In dialogue with Katrin Sieg’s work on ethnic drag and Amy Robinson’s theory of passing, I show how the film challenges ethnically-coded narratives of Germanness. In the final chapter on Nurkan Erpulat and Jens Hillje’s play Verrücktes Blut, I discuss how intertextuality and adaptation (Hutcheon, Genette) of different story and character worlds are used to create moments of ambiguity and overdeterminacy in the play, in order to challenge the audience’s perception of what an inclusive German society might look like.